Generally, free-standing block walls or fences are constructed of concrete blocks (or similar material) in running courses. A trench is usually dug and a concrete footing is prepared by the placement of batter or screed boards for forming a predetermined dimension for the footing's width and thickness. Horizontal reinforcing material, such as steel bars, running both laterally and transversally is tied together forming a cage within the screed board framework. The reinforcing material cage generally has vertical support elements that protrude above the screed board framework which will eventually tie into the vertical wall section and perform as a moment overturn resistance for the lateral forces acting upon the wall or fence structure. Concrete is then poured into the screed board framework and is leveled off so that it is flush with the screed surface. This leveling process can be difficult to achieve around the vertical support elements. The concrete is generally allowed to set for a time and then later a first course of blocks is laid using mortar to level the blocks on the concrete footing. Due to the irregularity of the footing with all the vertical support elements protruding through it, the first course usually requires the use of mortar at the bed and head joints of the blocks in order to ensure that the block is started in a level condition. Each subsequent course is placed in such a manner so that the vertical joints between blocks are staggered in a running bond pattern from a previous course. Mortar is used as a binding agent between the courses and between the ends of each of the blocks. Conventional concrete blocks typically have one or more voids or cores extending through them in the vertical direction to create open vertical columns through the walls. The vertical support elements are accommodated within these vertical columns. The blocks are installed by lifting them over the vertical support elements. The cores or voids are filled with grout to connect the wall to the vertical support elements of the footing to help ensure that the wall is stable. Additional reinforcing bars may be placed in these columns for enclosure with mortar or concrete within the columns, in accordance with building code standards and are connected to the vertical support elements of the footing to help ensure wall stability. Internally reinforced concrete walls may also be designed to utilize horizontal steel rebar reinforcing. Specific design location and steel bar sizing is determined by a qualified structural engineer according to project requirements.
In order for a wall constructed in this manner to be approved, a building inspector normally will require what is known as a “knockout”. A “knockout” is an inspection opening in a wall block at or near the base course. This requires that a portion of a block be removed in order to visibly ensure that the concrete grout has fully filled the entire vertical column.
Modular blocks used to build walls, columns, pillars and other structures are known in the art. Such blocks can be installed without special skill and are desirable because they are a convenient size to handle and have low installation costs. However, current methods of constructing walls with those blocks, and especially walls that require a concrete footing have numerous disadvantages. For example, these blocks typically must be used with masonry mortar at both head and bed joints to improve the structural integrity of a wall.
It would be desirable to provide a method for constructing a wall block or fence system with a support footing that is easy to install and can be used to construct mortarless walls, wall corners, fences, columns and other structures.
It would be further desirable to provide a method for constructing a wall block or fence system with a support footing wherein blocks of the wall or fence may be laid without first constructing the support footing prior to building the wall or fence. With conventional masonry walls known in the art, it is not possible to build the wall first and the footing later.
It would be further desirable to provide a method for constructing a wall block or fence system with a support footing wherein the reinforcing cage or framework of the support footing could be constructed after blocks have been laid.
It would be further desirable to provide a method for constructing a wall block or fence system with a support footing wherein concrete could be poured for the support footing after blocks have been laid.
It would further be desirable to provide a method for constructing a wall block or fence system with a support footing wherein concrete poured into columnar voids within the fence containing vertical support elements can be visibly verified to fully flow through the entire column without having to remove portions of concrete blocks near the foundation line.
It would further be desirable to provide a method for constructing a wall block or fence system with a support footing wherein concrete poured into columnar voids within the fence containing vertical support elements can encase the reinforcing cage or framework of the support footing.
It would further be desirable to provide a wall or fence constructed in accordance with the methods described herein.